diff --git a/requirements_test.txt b/requirements_test.txt
index a21e35097ca..942e38dad16 100644
--- a/requirements_test.txt
+++ b/requirements_test.txt
@@ -6,3 +6,4 @@
 flake8==3.6.0
 pytest==4.0.1
 mockcache==1.0.3; python_version < '3.0'
+